If you deploy Corvus and then deploy your squadrons at distance 2 of it but then redeploy Corvus such that the squadrons are not at distance 2 of any ship do you need to redeploy the squadrons or lose out on the ability to redeploy Corvus or does it just allow for squadrons to now start a game not at distance 2 of any ship?

You only need to deploy them at Distance 2.

Once they're deployed, its done.

You're not really checking again at any point.